Thermoplastics polymers have become ubiquitous in everyday life. For example, thermoplastic polymers are used in a variety of durable goods (e.g., home appliances, consumer electronics, furniture, and automobiles), consumable goods, and packaging materials for such goods. The ubiquity of thermoplastic polymers combined with an increase in recycling rates has enabled resin producers to introduce resin grades containing a significant amount of recycled material, such as post-consumer recycled (PCR) material (e.g., 25-50% PCR content). While these recycled resins are beneficial from a sustainability standpoint, the resins frequently exhibit diminished physical properties relative to 100% virgin resins. For example, the recycled resins typically exhibit lower impact strength and stiffness. Further, many recycled resins typically exhibit a relatively low melt flow rate (MFR), which can necessitate the use of a peroxide to increase the MFR into a desirable range for processing. However, increasing the MFR with a peroxide typically leads to further reductions in the impact resistance and stiffness of the recycled resin. Accordingly, when extant technologies are used in conjunction with recycled resins, one must strike a compromise between increasing the PCR content and undesirably decreasing the impact resistance and stiffness of the resulting polymer composition.
A need therefore remains for additives and processes that can produce polymer compositions having high recycled polymer content while maintaining, or even improving, the impact resistance of the polymer composition relative to compositions having lower recycled polymer content.